DE1658112B2 - PROCESS AND SYSTEM FOR BIOLOGICAL WASTE WATER PURIFICATION ACCORDING TO THE REVIVALATION PROCESS, IN PARTICULAR FOR FULL BIOLOGICAL PURIFICATION - Google Patents

Description

sern. ", Of your invention

To solve this problem, according to «*» the procedure of the type mentioned in ° f '. carried out that at least part of the j * m-iu Sludge before entering the phase * "" .. at least part of the course of the nose g

X claim 27, characterized

indicates that the second activated sludge tank (2) and the secondary clarifier (4) have a common one Have sludge sump (19) to which the Rucklaufschlammkana! (6) is connected. 29. Plant according to one of claims 11 to

28 characterized in that the secondary clarifier (4) with drainage channels (20) with horizontal or vertically arranged inlet slots is provided, the inlet slots in the manner are arranged and dimensioned so that the immersion depth of the ventilation rotors (15, 16) regulates automatically in proportion to the amount of water flowing off

30 Plant according to one of claims 11 to

29 characterized in that in the second activated sludge tank (2) and optionally in the secondary clarifier (4), especially in the lower area, transverse walls (29) perpendicular to the horizontal E ^ rd ^ iso in this process, in addition to the existing cycle phase I - ^ phase tU - && **

* ° if secondary clarifier phase Ibzw. ^{lle 'nz "Sd} ^ ~ _T circulation Phase I - return sludge line - Asel created * This has the advantage Dalj of." ^υ "" * sludge entering the Phase 1 mn acm s oxygen-containing end of the phase ι intimately S ". = "" »

"5 and therefore immediately exert its activity was running before he even in the area of ^Beluftu" S o ^{r sv} ™; niung enters the Phase I. Durcn Moreover α en additional circuit called the vernaiirru "Phase I stabilized" ^nd "^^" β. ^S ° _nner

3 <> sudden changes in the Zulaurvernaiimssc around halfway through phase I are absorbed and phase II is hardly affected. Another advantage is that in phase I ^a V * ^en Sr ",, large flocculent return sludge from ae _r ^ '

or the secondary clarifier and from small sludge from phase I in "£ ^{in S} °

Use invention relates to a method for biological Wastewater treatment according to the activated sludge process, in particular for full biological treatment, with splitting of the activated sludge stage, in which the water is circulated, charged with return sludge and is ventilated, into a heavily loaded activation phase (phase I) and a downstream, lightly loaded Activation phase (phase II), with the excreted from the sludge-water mixture of phase II Return sludge is partially introduced into phase I and partially into phase II.

Such a splitting of the activation stage has the meaning that in phase 1 with high pollution very short cleaning times, but not very thorough cleaning and poor sedimentation properties of the sludge, with the necessary further cleaning up to full cleaning and the flocculation of the sludge can then take place in the second stage. This will be effective at and also particularly good sedi These advantages contribute overall to the sought-after improved adaptability and efficiency of the process.

Preferably, ^the _TT ^tal g _f ^e .J ^ "However ^g _return _ phase I and phase II zügeff ^hardships f ^ ™. Sludge with the Ge" mtabbu ^ Ph ase I ge mixed in. This closing "'^^',"Xhlammes supply of a ^z - ^ f _p ^e ^^ to phase 1 and / or phase 11 ™ * ° J} ™ * · \ above-mentioned mixing process sta

In further voiteüh ^ excellent ^ 8 ^.

phase I and rna g

led subsets of the mixture in inre g

independently f ^e "f" j "^ s dner the sludge may consist of phase ITund / or a" ener Phase II downstream Nachklarstute active

to be pulled. Es ^ J ™ ^^ 3 " _before . Mud pollution .n Phase Ib szu ^ ehnmalvo

preferably up to five times ^un ^ ~ ° "X _W1 ^. twice larger as - phase ι emg ^ rege

In phase II whose iui iui favorable conditions ^ f

the aeration tank containing phase II and which is produced, whose

one

5 ^b 6

Is zero or close to zero. The flow velocity 3) is constantly part of the activated sludge mixture

The speed on the surface is expediently 20 subtracted from the aeration tank 1. It gets

up to 50 cm / sec. into a mixed duct leading vertically upwards

A sludge activation system for carrying out min 3. This mixing chimney 3 is

of the method according to one of claims 1 to 10, 5 running sludge channel 6 return sludge from the ge

with a first sludge sump 19 of the activated sludge tank, which is shared with aeration

Henen aeration basin and a second with basin 2 and the secondary clarification basin 4. This

ventilation facilities provided aeration basin, sludge sump 19 is deeper than the bottom of the

which are connected by a conveyor is activated sludge tank 1, and the upward conveyor

according to the invention characterized in that the ¹⁰ takes place through the return sludge channel 6 through the

Inflow of the conveying device to the first activation hydrostatic pressure of the water in the secondary clarifier

basin and a return sludge channel and their ken 4 on the settled sludge that passes through the

Discharge to the first aeration tank and to the gases evolving with it specifically becomes easier

second aeration tanks are connected. than the pressing water for him. This hydrosta-

In a particularly advantageous manner, an ^X 5 table conveying effect is achieved by being pointed downwards

intimate mixing of the sequence of phase I with the tapering profile of the sludge 19 reinforced.

Rücklaufschiamm in such a way that the conveying an additional conveying effect takes place in the

direction as perpendicular and / or obliquely upwards return sludge channel 6 and in the mixing chimney 3

render mixing chimney is formed. instead of the supply of compressed air through a

To regulate the sludge load in phase I ^ao collecting line 9 and individual lines 8 are supplied

the mixed chimney, preferably its drain, is arranged with and through directly on the pool wall.

Aeration boxes open at the bottom, sunk by an excess sludge extraction device, in which

hen, which is expediently a comb shape at the upper end of the at least part of a side wall

Mixing chimney, preferably on the side of the first with downwardly open spaces, exits.

Activation tank is arranged and designed as ^a channel 5 The air thus occurs uniformly on the entire

forms is. Girth spread out, being by the choice of width

To ventilate the aeration basins, the desired spacing and spacing can be used known ventilation rotors can be provided, the amount of air and the size of the bubbles being able to be influenced. These in contrast, that in the first aeration tank and in the second BeIe ensures the type of air entry Ventilation rotors arranged in the exercise pool a 3o to perforated pipes and other closed Beifferent Have ventilation performance. ventilate the greatest possible freedom from clogging, since

An embodiment of a sludge revitalization tuell on those that get stuck in the interstices

Plant according to the invention is shown in the drawing fibers, textiles. Hair or the like, through the air after

and is explained in more detail below. It shows being displaced below. In addition, the

Fig. 1 the plan, 35 order of the individual lines 8 as recesses in

F i g. 2 shows a section approximately along the line II-II of the outer pool wall of the aeration tank 1

Fig. 1 and any obstruction of the free flow or the free

3 is a sectional perspective view. Buoyancy in the mixed chimney 3 avoided.

The sludge activation system consists of a through the air supply is the return sludge

first, rectangular, ring-shaped closed BeIe- 4 ° conveyed upwards and simultaneously with the through

exercise basin 1, an aeration basin 2, which flows through the openings 5 of the aeration

the aeration basin 1 rectangular-ring-shaped around basin 1 intimately mixed and aerated. This represents

there, and a secondary clarifier 4, which is the second effective mixing circuit. By supply

Exercise pool 2 also in the form of a rectangular ring with more or less compressed air through the pool!

Ges surrounds. This results in a compact 45 line 9 is a control of the mixing channel

Arrangement of the basins. However, every other, min 3 amounts of return sludge and

Ring-shaped, closed arrangement of the basins possible- Waste water possible.

Huh From the mixed chimney 3, the mixture is partially

The wastewater to be cleaned is extracted from the wastewater via an overflow edge 10 into the aeration tank 1

water inlet 23 via a culvert line 17 and a 5o and via an overflow edge 11 into the activation tank

Cross channel 18 fed to the activated sludge tank 1, and ken 2 promoted. The ratio of the

although flowing in the direction of flow directly in front of a basin 1 and the aeration basin 2

ventilation rotor 15. It is therefore immediately from the show quantities can be regulated by appropriate

finely detected the ventilation rotor 15 and with the adjustment of the overflow edges 10 and 11, the length

Aeration basin 1 circulating sludge-water 55 and / or height.

Mixture mixed thoroughly. This arrangement represents it is both the aeration tank 1 as

therefore an effective first mixing circuit. Also the activated sludge tank 2 and return sludge

As FIG. 1 shows, the activated sludge tank 1 is also a corresponding part of the activated sludge tank the transverse center line symmetrically formed I supplied constant flowing mixture, det, so that at both ends of the activated sludge tank 1 & »To regulate the sludge content in the activated sludge tank Water inlet takes place. Further aeration tank 1 is transferred from the one in the aeration tank 1 Ren can, depending on requirements, at other points of the overflowing activated sludge mixture through the Ent-Bekbur.gsbeckens 1 be arranged. The aerated, speaking arranged openings 12 along the BeleHschlammlösung circulates in the BeleHschlammkammer 10 excess sludge in a channel ken 1 with an adjustable 65 13 derived depending on the requirements, with the excess amount to be dispensed γπιπΚ'κτ. Dwell time. sludge-tight by slide 14 can be metered. Of the

Along the circumference of the activated sludge tank 1, the remainder of the overflow edge 10 into the activated sludge

distributed bottom-side openings 5 (see. Fig. 2 and basin 1 flowing back subset is through the

Ventilation rotors 15 mixed again with the basin contents.

One sets the overflow edges 10, 11 and the slide 14 so that in the aeration tank 1 one Relatively low activated sludge concentration and one in the activated sludge tank 2 high activated sludge concentration is maintained. The load is therefore in the aeration tank 1 of the activated sludge with pollutants to be degraded large, which is the conditions of a rapid, but corresponds to leading biological degradation only up to a partial cleaning. In the aeration tank 2 takes place then with low pollution of the activated sludge present in high concentration the degradation up to biological full cleaning.

The over Jie overfall edge 11 into the activation basin 2 f! Ic! 3ende subset is there by a ventilation rotor 16 mixed with the basin contents and aerated. This represents the third mixing circle. The Aeration rotors 16 in the aeration basin 2 can be independent of the aeration rotors 15 of the aeration basin 1 and can also be arranged in other places. However, the one shown is advantageous Arrangement in which the aeration rotors 16 in the aeration tank 2 simple extensions of the Represent aeration rotors 15 of the aeration tank 1. In the aeration tank 2, the oxygen input should and the turbulence will be less than in the aeration tank 1. This is expediently done by A smaller number of plates of the ventilation rotor 16 is achieved. By equipping the ventilation rotor 16 and also by installing transverse walls 29 in the lower area of the activated sludge tank 2, which can continue in the secondary clarifier 4 the horizontal circulation in the aeration tank 2 promoted so that the horizontal flow rate decreases continuously from the pelvic surface downwards and reaches almost zero in the lower area. The flow rate at the surface is expediently about 20 to 50 cm / sec.

The flow in the aeration tank 2 goes into a practically no component in the lower area Longitudinal direction of the basin taking place overflow, which initially downwards through the obliquely after downwardly directed openings 22 leads into the secondary clarifier 4, where it merges into an upward flow, which is particularly favorable for the sedimentation of the sludge.

In order to keep the sludge concentration high in Beiebungsbeckken 2, there is normally no excess sludge taken. This creates favorable conditions for the sludge to circulate. The activated sludge flakes formed separate from the biologically cleaned one in the secondary clarifier 4 Sewage and settle.

For the drainage of the water from the Nachklärbek ken 4 are distributed drainage channels on the surface 20 provided, from which the water can flow through a collecting channel 21 into a receiving water. Dk Drainage channels 20 have inlet slots that are designed and dimensioned to se the immersion depth the aeration rotors 15 and 16 automatically adjusts to the amount of water running off. An additional Adjustment of the air intake performance to requirements can of course be done by changing the Speed of the ventilation rotors 15, 16 or preferably by connecting or disconnecting individual rotor units being controlled.

The whole system is preferably composed of precast concrete parts. The ventilation boxes used 7 can be made of an insensitive material such as concrete, asbestos, cement, plastic

^a ° or steel.

The method for wastewater purification can be carried out on such a system, for example according to the following figures are carried out. If there is an attack of medium to thin domestic ahwas-

»5 a sludge concentration of 1 to 1.5 kg dry matter per m ^{3 is} maintained by appropriate adjustment of the corresponding control organs in the aeration tank 1, corresponding to a sludge load of 2 to 3 kg BODj per KiIo-

grams of dry matter. By the proportionate low sludge concentration results in a small energy requirement for the circulation and turbulence. The high sludge load results in high degradation activity and thus rapid degradation of the

Sludge to a degree of biodegradation of 75 to 85 %. The horizontal circulation in the activation tank 1, which is kept going by the aeration rotors, takes place at a speed of 30 to 50 cm. With a pool length of, for example

4 = ju m and a mean residence time in the basin of one hour the mixture circles about 15 times.

In the activated sludge tank 2, by appropriate regulation of the return sludge delivery, in particular by adjusting the delivery rate of the pressure

air pump, generates a high sludge concentration of 5 to 8 kilograms of dry matter per m 'and maintain. The horizontal flow velocity is 20 to on the surface 25cm / sec and decreases rapidly downwards. In this

In the case of a small sludge load, the basin then breaks down the ReSt-BOD _{5 of} the drain from the aeration basin 1 until it is fully biologically cleaned

Instead of.

1 sheet of drawings

309517/432

Claims (27)

Patent claims: 1. Process for biological wastewater treatment according to the activated sludge process, in particular for full biological cleaning, with splitting of the activation stage in which the water circulates, is charged with return sludge and aerated, in a highly loaded activation phase (phase I) and one of these downstream lightly loaded activation phase (phase Π), where the off the sludge-water mixture of phase Π partially separated return sludge in the Phase 1 and partially in phase Π is initiated, characterized in that at least secs a portion of the return sludge prior to entering phase I and II with at least one Part of the sequence of phase I is intimately mixed. 2. The method of claim 1, characterized overall ^ao indicates that the total amount of the phase I and phase II supplied to the return sludge is mixed with the overall flow of Phase I. 3. The method according to claim 1, characterized overall ^a 5 indicates that the phase I and phase II supplied parts of the mixture are controlled independently of one another in their quantity. 4. The method according to any one of claims 1 to 3, characterized in that the return sludge of phase II and / or from one of the Phase II downstream clarification stage is withdrawn controllably. 5. The method according to any one of claims 1 to 4, characterized in that the oxygen input in phase I is independent of the oxygen input is regulated in phase II 6. The method according to any one of claims 1 to 5, characterized in that in phases I and II upheavals with independently of one another adjustable flow rate can be generated. 7. The method according to claim 6, characterized in that in phase II with a circulation a flow velocity is generated, the horizontal component of which has a maximum value decreases downwards in the area of the water surface and preferably zero in the lower area or close to zero. 8. The method according to claim 7, characterized in that the flow rate in 5 < > Phase I in the area of the water surface is 20 to 50 cm / see. 9. The method according to any one of claims 1 to 8, characterized in that the sludge load in phase I up to ten times, preferably up to five times and especially up to twice larger than is regulated in phase II. · 10. The method according to any one of claims 1 to 9, characterized in that the sludge load in phase I _{is regulated over 1.5 kg BOD 5} , in particular over 2 kg BOD ₅ per kilogram of dry matter, provided that the full biological cleaning conditions in phase II are complied with. 11. Sludge activation system for carrying out the method according to one of claims 1 to 10, with a first aeration basin and a second aeration basin provided with aeration devices, which is conveyed by a conveying device are connected, characterized in that the inflow of the conveyor to the first Aeration basin (1) and a return sludge channel (6) and its drain to the first Aeration basin (1) and the second aeration basin (2) are connected. 12. Plant according to claim 11, characterized in that the conveyor device as perpendicular and / or a mixing chimney (3) leading obliquely upwards. 13. Plant according to claim 12, characterized in that the mixing chimney (3), preferably whose drain is provided with an excess sludge removal device. 14. Plant according to claim 13, characterized in that the excess sludge removal device at the upper end of the mixing chimney (3), preferably on the side of the first activation tank (1), arranged and designed as a channel (13). 15. Plant according to claim 14, characterized in that that the channel (13) for the excess sludge has a controllable drain at at least one end, which is preferably through a slide (14) can be shut off. 16. Plant according to one of claims 11 to 15, characterized in that on the drain or the outflows of the conveyor device adjustable overflow edges (10, 11) are arranged. 17. Plant according to claim 16, characterized in that the overflow edges (10, 11) in adjustable in height or length. 18. Plant according to claim 14 or 15, characterized in that the channel (13) for the excess sludge at the same time forms an overflow edge (10) for the outlet of the mixing chimney (3). 19. Plant according to one of claims 11 to 18, characterized in that the conveying device has a mammoth pump in a manner known per se. 20. Plant according to claim 19, characterized in that the mammoth pump one after Has a ventilation box (7) open at the bottom, in which at least part of a side wall has a Has a comb shape with spaces open at the bottom. 21. Plant according to one of claims 11 to 20, characterized in that aeration rotors known per se for ventilating the aeration basins (1, 2) (15, 16) are provided. 22. Plant according to claim 21, characterized in that the ventilation rotors (15, 16) a different aeration capacity in the first aeration tank (1) and in the second aeration tank (2) exhibit. 23. Plant according to claim 22, characterized in that one or more of the existing Aeration rotors (15, 16) with a section in the first aeration tank (1) and with another section is immersed in the second aeration tank (2), the sections have different plates. 24. Plant according to one of claims 11 to 23, characterized in that the activation tank (1,2) are each closed in a ring shape. 25. Plant according to claim 24, characterized 3 ^T 4 indicates that the second activated sludge tank phase I and Π containing activated sludge tanks are included kWif * ^ g ^ E% £ & Sä 26. Plant according to claim 25, characterized in that the flow from the first activation tank (1), the mixing with the return sludge and the feed of the mixture to the first activated sludge tank (1) and to the second activated sludge tank (2) evenly distributed along at least part of the outer circumference of the first activation tank (1) or the inner circumference of the second activated sludge tank (2), preferably along the entire circumference. 27. Plant according to one of claims 24 to 26, characterized in that a secondary clarifier (4) the second activated sludge tank (2) ringteade load fluctuations relatively wemg ^ adaptable, which is why ui these traps cue äcuu _{S b} performance of this process relatively low The object of the invention is zug * ™haben · ._ Procedure of the type mentioned "! ^ ™ ™ ^c " * " adaptability to « ⁿ ^ ^{sdne <} ? ^l 5f "and with regard to its power of stimulation